The invention generally relates to air bags for safety restraint systems as well as to a method of folding an air bag used to protect an occupant in a side impact or crash.
Many side impact air bags are installed within the outer portion or wing of an occupant seat or fascia of a door adjacent the seat. Upon inflation, the air bag must tear through the seat""s covering material (or door fascia) and thereafter position itself at the proper orientation to protect the occupant during the side impact collision. The positioning of the air bag within the seat and the construction of the covering material have an effect on the way the air bag inflates.
Additionally, it is well known in the art that the method of folding affects the trajectory of the inflating air bag.
One of the design criteria for side impact air bags is an improved interaction with the out-of-position occupant, that is, the occupant that is not in the normal, upright seated position. While adults will generally be seated upright or perhaps seated leaning over against the adjacent door, children are apt to be seated in many unusual positions.
It is an object of the present invention to provide an improved air bag and air bag module which utilizes an improved method of folding the air bag such that the head chamber of the air bag is deployed in a more vertical direction, thereby reducing any forward or longitudinal component of force exerted by the deploying air bag on the occupant and more particularly on an occupant that is out of position.
Accordingly the invention comprises: a method of folding an air bag, the air bag having facing first or upper and second or lower panels that are joined together, a portion of each panel cooperating to form a neck or inlet which is adapted to receive an inflator, the method comprising the steps of:
a) arranging the first and second panels to be generally flat on a work surface with a first panel overlaying a second panel;
b) defining a first horizontal fold or tuck line in the first panel;
c) identifying an upper portion of the first panel that is located above the first fold line, and tucking this upper portion behind a lower portion of the first panel and pushing a part of the upper portion generally to the bottom of the air bag, the tucking of the upper portion at the first fold line creating a first fold or tuck in the first panel at the first fold line and the moving the first panel to the bottom creating a second fold near the bottom, the first panel extending from the second fold, beyond the first fold line so that the top of the air bag is a determinable distance from the first fold line; the above step lowering the height of the air bag in relation to its laid-out configuration in step a;
d) identifying a first vertical fold line in the upper portion of the air bag, this first fold line generally extending across the upper portion from the second fold to the top of the air bag;
e) folding the upper portion generally about the first vertical fold line to reduce the width of the upper portion;
f) folding or rolling the upper portion toward the first fold line, the folding forming a fabric roll, the fabric roll after the rolling or folding of this step is positioned generally in line with the first fold line;
g) rotating the fabric roll so that an end there that was pointing toward the inflator is positioned facing the bottom of the air bag and a top of the roll now lying adjacent the location of the inflator;
h) moving a portion of the air bag generally opposite the repositioned fabric roll toward the location of the fabric roll and in doing so, forming two opposing pleats in the upper and lower panels, wherein both of the pleats are positioned to lie behind the fabric roll, that is, positioned closer to the lower panel;
i) identifying an angled fold line in the partially folded air bag
j) moving a corner of the air bag about the angle fold line generally toward the inflator to form a generally trapezoidal configuration of the folded air bag; enveloping the air bag with a tearable cover. Many other objects and purposes of the invention will be clear from the following detailed description of the drawings.